Building savoury depth deliberately
A short list of ingredients that do most of it.
Depth in a meat dish comes from browning and from the meat itself. Without it, the same effect is built from ingredients rich in glutamates and from the same browning applied elsewhere, and a handful of items do most of the work.
Tomato paste cooked in oil until it darkens from red to brick is transformative and takes two minutes. Dried mushrooms, soaked and with the soaking liquid used, add more than fresh. Miso, soy and tamari contribute directly. Aged hard cheeses, where the diet permits them, are among the most concentrated sources available.
Layering matters more than quantity. A dish with three modest savoury contributions at different stages tastes deeper than one with a large amount of a single ingredient, which tends to announce itself.
Note that many traditional savoury ingredients contain fish, including several fish sauces and some Worcestershire sauces and cheeses made with animal rennet. Where that matters, checking the specific product is necessary, since it varies by brand.
It is worth adding that savoury depth can be built in advance and kept. A jar of caramelised onions, a batch of browned mushrooms, or a paste of cooked tomato and aromatics will improve everything it is added to for a week, and it moves the time-consuming step out of the weeknight where it cannot happen.